Palladium‐Catalyzed Enantioselective Intramolecular Hydroarylation of Alkynes To Form Axially Chiral 4‐Aryl 2‐Quinolinones

A long-awaited asymmetric version of the intramolecular hydroarylation of alkynes to form fused ring systems has been developed. A cationic palladium(II)/(S)-xyl-H8-binap complex was used to catalyze an enantioselective hydroarylation of alkynes at room temperature to furnish axially chiral 4-aryl 2-quinolinone derivatives in good yields with good enantioselectivity (see scheme; Bn=benzyl).